Temperature compensation of resonant accelerometer via nonlinear operation

This paper reports a simple, effective method to improve the bias stability of a resonant accelerometer over a large temperature range. By using the nonlinear amplitude-frequency effect, this technique further reduces residual temperature dependence of a passively temperature-compensated differential signal from two sensing resonators. Driving one resonator beam with a large excitation amplitude into the nonlinear regime moves its frequency-temperature characteristic closer to that of the other sensing beam. Preliminary results show a near fivefold improvement in 0g bias stability while maintaining high sensitivity and scale factor stability over the temperature range from -20°C to 80°C.